Upgrading system?

Inconspicuous

Hi,

I'm looking for a little help/advice. Its coming into winter again and I'm looking at our heating system. We currently have a GFCH system with a gas fire in the sitting room. We've never used the fire in the sitting room as I see it the same as throwing a bunch of 20 euro notes in the fireplace and lighting them on fire.

Our house was built in the late 90's and as such has a basic enough central heating system. The gas boiler is in the utility room and has a basic timer fitted beside it. There is a thermostat in the hall, but I've no idea if this actually functions. The boiler is plumbed to the rads and to the hot water tank in the hot press. During the summer we are able to close a valve that directs all the hot water from the boiler to the hot water tank, bypassing the rads. This is about all the control we have over our system at the moment.

The wife really wants a fire in the sitting room and has set her mind on a wood burning stove. This suits me too as I've always liked having a fire on cold winter evenings.

Now that I've looked into it though, I'm starting to convince myself that I should probably look into upgrading the entire heating system in the house.

Insulation aside, I'm thinking of possibly doing the following:

1: Removing the current hot water tank and inserting a thermal store instead with optional inputs for different heating sources (possibly solar at a later date) and plumbing the gas boiler to this.

2: Installing a wood burning stove in the sitting room with a back boiler and having this plumbed to the thermal store.

3: trying to create a "zoned" heating system by inserting controlled valves into the system to basically give me a downstairs zone and an upstairs zone. This would be managed by thermostats and an intelligent controller with schedules and timers.

The idea behind this is to effectively use our heating resources a little more efficiently by not continuously heating the whole house all the time when we are only using a certain part of it. Also, if I'm going to now be burning wood as a heat source, I like the idea of trying to maximise on this as much as possible.

What I'd like to know is if I'm on the right track here. I've absolutely no experience in this area so I guess what I have laid out above is a bit of a wish list. Does anybody here know if what I'm proposing is possible? Has anybody tried to create this sort of a system before, especially in an existing house (ie not a new build)?

Also, I'd be very grateful if somebody could recommend a good heat engineer or plumber in the greater Dublin / Meath / Kildare area who could advise me on this and help me plan out a system that will meet our needs.

Any comments or advice or just telling me I'm plain mad would be great!

Thanks!

JD6910

Would love to see posts on this item from the experts out there!!!!!

shane0007

You are trying to achieve a lot within one system and for what you require you will need dedicated space. Solid fuel and gas don't mix well but is achievable however at a cost.

It is one of those systems that is difficult to ascertain without physically looking at the system in hand and is probably why you are not receiving many replies.

I am not a lover of thermal stores as whole of the store must be maintained at high temperature to heat the DHW coil within the store. Most users of them are dissatisfied with their performance. A buffer with a separate DHW cylinder is a far better choice.

Inconspicuous

Thanks for the reply Shane, I appreciate your input.

Like I said, I've no real experience in this area so was just sounding out a few ideas. What really started all of this was that we want to put a stove in the sitting room and it kind of spiraled from there

I was surprised to hear that thermal stores are not giving the expected results and that people were not happy with them. I've definitely not got my heart set on this so that can be scrapped straight away!

I like the idea of using the heat from the stove to help supplement the heating system of the whole house. I know you said that gas and solid fuel don't work well together, but I take it that it may actually be possible, but with a lot of work? Do you think that in the end this work would actually be worth it or should I just install a stove in the sitting room which would just heat that room and possibly the room adjoining it?

Also, I would love to hear your views on my idea of trying to create zones in the house using valves and timers. Is what I'm saying actually possible?

Ideally I want to have somebody come out to my place and take a look at the system and tell me what can and can't be done. Do you (or anybody else for that matter) know of good reliable independent engineer/plumber who may be able to advise me?

Thanks again for all your help.

shane0007

Zoning can be achieved but certain precautions must be adhered to when solid fuel is introduced. The zone valves must not form any part of the solid fuel circuit and no TRV's are allowed on any radiators.

Whether it can be safely installed in your particular installation, I could answer that after actually seeing it.

ccsolar

Hi
I have all of the above done in my house this year
We have a solid fuel stove feeding a 300 litre tank, (hadn't room for a bigger 1)
We also upgraded the old oil boiler to a condensing 1, ( the old boiler was 26 years old but hadn't any insulation)
Obviously I have the solar in which covers the summer months but also Pre heats the water to 30 degrees in winter.
We fitted Honeywell HR40 rad stats in the rooms that were only been used frequently and the bedrooms also.
The results were as follows,
The HR40 TRV were only allowing the rads to operate when requested therefore the oil boiler had less work to do.
The oil boiler heats the tank first then the rads but as most of the rads are now controlled the oil boiler is heating the 300 litre tank 9 degrees hotter but I never changed the settings on the boiler thermostat.
The solid fuel stove has only been tested in the last few days even though it's been fitted a few months, ( well the stove was fitted but we could only afford to buy the Chimney flue 2 weeks ago , have pictures of stove with no flue to prove this to the skeptics ,anyway )
We fired up the stove a few days ago and it automatically takes over from the oil boiler, we have it set up to heat the tank first then the rads
I like to test these things out so without much feeding I got the stove to heat the tank to 81 degrees the other night ( the solar had it at 53 degrees ) then switched to the rads , the whole house was hopping including the wife had to open the doors to let out the heat.
I noticed the oil boiler came on with the timer but switched off after about 30 seconds and did not come back on again that night , it came on again with the timer the following morning but switched off again almost immediately .
I expect to burn no oil this winter unless it's inconvenient to light the stove.
I have only used 2 x 10 litre buckets of ****ty timber from pallets for these results, it's an Inis mor stove (big beast)
It takes 1 bucket to fill it....
The house is a 1930 cottage done up and has a B3 rating
I'm in Galway so if you want to have a look at the set up here were only down the motorway,
O, 1 last thing
Get advice from stoveman on the size of your stove ..
Cc

shane0007

ccsolar wrote: »

We fitted Honeywell HR40 rad stats in the rooms that were only been used frequently and the bedrooms also.

I like to test these things out so without much feeding I got the stove to heat the tank to 81 degrees the other night ( the solar had it at 53 degrees ) then switched to the rads , the whole house was hopping including the wife had to open the doors to let out the heat.

You should not have any TRV's fitted on any radiator where solid fuel is installed. The HR40 can indeed achieve boiler interlock with the oil boiler but it cannot turn off the solid fuel back boiler.

Honeywell specifically states that you should not install the HR40 in an installation that has solid fuel installed. If they is a power cut, all HR40's go to the closed position and when the time lock is in the off mode they are also in the off position and should the solid fuel be lit, you could have problems.

ccsolar

shane0007 wrote: »

You should not have any TRV's fitted on any radiator where solid fuel is installed.

If the above quoted statement is true then half of the households in the country will have to dispose of their solid fuel stoves with back boilers. In this case anybody who anticipates availing of a grant from the SEAI for heating control upgrades should forget about it as this would require TRV"s fitted on a number of radiators.

The back boiler works on a gravity circuit between the stove and the back boiler with expansion into the attic if the system gets too hot. You should also fit a pressure release valve at the rear of the stove which is piped externally as a second safety measure. You could also fit a radiator off the return for dumping heat (an open circuit). With regards to the solid fuel/central heating you would need to install a circulating pump and motorised valves for zoning the upstairs and downstairs (this set-up will not work in the case of no electricity). Solid fuel will not travel around to the rads without help from a circulating pump.

If there is a powercut you can also close the air inlet for the stove which will practically extinguish your fire or reduce it's performance drastically, Stovefan would know more about this.

shane0007 wrote: »

The HR40 can indeed achieve boiler interlock with the oil boiler but it cannot turn off the solid fuel back boiler. Honeywell specifically states that you should not install the HR40 in an installation that has solid fuel installed. If they is a power cut, all HR40's go to the closed position and when the time lock is in the off mode they are also in the off position and should the solid fuel be lit, you could have problems.

The HR40 cannot affect anything outside of the room that it is installed in as it is battery operated. However, you can connect it to the HN40 which only replaces the batteries that last around 2 years. Unless you fit the HN40 a powercut will have nothing to do with your HR40 TRV"s

Solid fuel back boilers have been around for years and work in conjunction with oil OR any other heat source when installed correctly. The latest stoves on the market are very capable of handling any powercut if the system is plumbed correctly and now you can also buy a pressurised solid fuel stove from Germany. Dont know much about these as I have only seen one installed but it worked fine. I have worked on numerous properties over the years with solid fuel back boilers installed and working in conjunction with oil, gas and solar and have yet to see any of the problems warned of in the above quoted post

I was replying to a post by Inconspicuous but it only took 30 minutes for it to get shot down. I am not suprised that some very knowledgeable posters in their fields have stopped giving their advice. There are a lot of scaremongers out there Inconspicuous!!!

The water from the solar system in my own house is currently at 58 degrees so no need to turn on oil tonight or light the stove!!

http://products.ecc.emea.honeywell.com/europe/pdf/en2h0169ge51r0901.pdf

Cc

shane0007

ccsolar wrote: »

I was replying to a post by Inconspicuous but it only took 30 minutes for it to get shot down. I am not suprised that some very knowledgeable posters in their fields have stopped giving their advice. There are a lot of scaremongers out there Inconspicuous!!!

Cc

Hmmmm.... nice

Inconspicuous

Lads,

Sorry for the delay in getting back to you. Bit of a hectic time at the moment!

Shane, I'm curious to know why zone valves cannot be installed on a system with a solid fuel heat source? I was under the impression that zone valves could be used and that any excess hot water gets diverted firstly to the hot water tank and then out to an expansion tank? I thought that the hot water tank/thermal store would act as a "dump" for the excess hot water not being used by the heating system.

ccsolar, your set-up sounds pretty much exactly what I'm looking for. But just so I understand you correctly. The way your system sounds to me is that all of your heat sources heat your tank first. Once your tank reaches a certain temperature, the heat sources then heat your rads? Is this correct? Does this mean that you have 2 circuits? I'm not sure if I'm making sense, so sorry if I'm confusing the situation.

What sort of tank do you have if you don't mind me asking?

Again thanks for all the opinions lads, its really helpful. I've gotten a recommendation of a good plumber in the area so will be contacting him shortly. I just want to have my head straight about what I would like my system to do vs what is actually possible before I talk with him.

shane0007

Inconspicuous wrote: »

Lads,

Sorry for the delay in getting back to you. Bit of a hectic time at the moment!

Shane, I'm curious to know why zone valves cannot be installed on a system with a solid fuel heat source? I was under the impression that zone valves could be used and that any excess hot water gets diverted firstly to the hot water tank and then out to an expansion tank? I thought that the hot water tank/thermal store would act as a "dump" for the excess hot water not being used by the heating system.

ccsolar, your set-up sounds pretty much exactly what I'm looking for. But just so I understand you correctly. The way your system sounds to me is that all of your heat sources heat your tank first. Once your tank reaches a certain temperature, the heat sources then heat your rads? Is this correct? Does this mean that you have 2 circuits? I'm not sure if I'm making sense, so sorry if I'm confusing the situation.

What sort of tank do you have if you don't mind me asking?

Again thanks for all the opinions lads, its really helpful. I've gotten a recommendation of a good plumber in the area so will be contacting him shortly. I just want to have my head straight about what I would like my system to do vs what is actually possible before I talk with him.

Because your solid fuel boiler should be sized to heat the load installed and if it is partly closed down with either zone valves or TRV's, it encourages pitching which oxygenates the heating system. This leads to internal corrosion and is conducive of a poorly designed system. Check the colour if the heating water and/or the colour of contaminants within the circulating pump. It will tell a lot about what is happening within your system behind the scenes. It will either be reddish colour, black or clear.

ccsolar

Inconspicuous wrote: »

Lads,

ccsolar, your set-up sounds pretty much exactly what I'm looking for. But just so I understand you correctly. The way your system sounds to me is that all of your heat sources heat your tank first. Once your tank reaches a certain temperature, the heat sources then heat your rads? Is this correct? Does this mean that you have 2 circuits? I'm not sure if I'm making sense, so sorry if I'm confusing the situation.

Yes, All my heat sources heat the tank first then when the tank has reached the desired temperature the heating kicks in.
The primary line from the stove only heats the tank and the secondary line heats the rads using a circulating pump.

Inconspicuous wrote: »

What sort of tank do you have if you don't mind me asking?.

I have a 300 litre triple coil stainless steel tank but would have fitted a Multi-fuel stratification tank with 2 coils if I had the space in the hotpress.
The Multi-fuel tanks are the way to go but cost around €1800 to buy.
If you are worried about corrosion in your heating system you should look at putting in some Fernox anti-corrosion for protection.
Sorry now for the short reply but were very busy with work..

Cc

freddyuk

Inconspicuous wrote: »

Hi,

I'm looking for a little help/advice. Its coming into winter again and I'm looking at our heating system. We currently have a GFCH system with a gas fire in the sitting room. We've never used the fire in the sitting room as I see it the same as throwing a bunch of 20 euro notes in the fireplace and lighting them on fire.

Our house was built in the late 90's and as such has a basic enough central heating system. The gas boiler is in the utility room and has a basic timer fitted beside it. There is a thermostat in the hall, but I've no idea if this actually functions. The boiler is plumbed to the rads and to the hot water tank in the hot press. During the summer we are able to close a valve that directs all the hot water from the boiler to the hot water tank, bypassing the rads. This is about all the control we have over our system at the moment.

The wife really wants a fire in the sitting room and has set her mind on a wood burning stove. This suits me too as I've always liked having a fire on cold winter evenings.

Now that I've looked into it though, I'm starting to convince myself that I should probably look into upgrading the entire heating system in the house.

Insulation aside, I'm thinking of possibly doing the following:

1: Removing the current hot water tank and inserting a thermal store instead with optional inputs for different heating sources (possibly solar at a later date) and plumbing the gas boiler to this.

2: Installing a wood burning stove in the sitting room with a back boiler and having this plumbed to the thermal store.

3: trying to create a "zoned" heating system by inserting controlled valves into the system to basically give me a downstairs zone and an upstairs zone. This would be managed by thermostats and an intelligent controller with schedules and timers.

The idea behind this is to effectively use our heating resources a little more efficiently by not continuously heating the whole house all the time when we are only using a certain part of it. Also, if I'm going to now be burning wood as a heat source, I like the idea of trying to maximise on this as much as possible.

What I'd like to know is if I'm on the right track here. I've absolutely no experience in this area so I guess what I have laid out above is a bit of a wish list. Does anybody here know if what I'm proposing is possible? Has anybody tried to create this sort of a system before, especially in an existing house (ie not a new build)?

Also, I'd be very grateful if somebody could recommend a good heat engineer or plumber in the greater Dublin / Meath / Kildare area who could advise me on this and help me plan out a system that will meet our needs.

Any comments or advice or just telling me I'm plain mad would be great!

Thanks!

All this is possible and would be very effective if it was sized and installed correctly. A thermal store is a great idea but your DHW is the key thing as you need this on tap at all times so treat this as priority. The space heating could come from the thermal store but in practice it would need to be pretty big to heat all the radiators as it is far more effective for low temperature underfloor heating. Radiators would strip the heat out very quickly. So better to zone the house correctly so you are not heating rooms you don't use or need to be hot. Putting all the heat resources into one cylinder saves on space but may not be practical if you are installing a WBS as you want this to be directly below the store to work off gravity effectively.Your solar will keep the store nicely prewarmed so the boiler will only be topping up the heat if required.
You do not need to keep the whole thermal store hot to be effective you just need an external heat exchanger which picks up the heat from the top of the store where the boiler will ensure there is always sufficient hot water. The solar and WBS would input free heat when it was available. To be told that a thermal store does not work and everyone is unhappy is nonsense.
I have a buffer tank above the WBS with solar input which then feeds the DHW cylinder where the boiler tops up if required. I have the WBS directly connected to the buffer so it is flowing through the whole cylinder into the top and out the bottom. There is a safety circuit if required. This means I have two coils for solar thermal where I can top load the heat into the top of the cylinder first and then the bottom so the heat is always available from the take off point. If you have mains pressure you can use the outside heat exchanger but I am well fed so need to pump everything.
Get someone to look at your house and work out the best plan and then decide. I replumbed quite a bit to get it right but it all works fine.
You cannot do this from a forum post but you can pick up ideas and configure them for best results into your system.
More control will reduce wasted heat and is cheap to install the first time but not easy to retrofit. Your ideas are absolutely on the right lines.
Don't forget insulation and draught proofing is also vital to keep bills down and is cheap to do.